Determination of nitrogen (N) available in the soil

Nitrogen (N) is the nutrient that most limits the production of sugarcane in the soils of the flat part of the Cauca river valley.

So far the recommendation of nitrogenous fertilizers in the sugarcane production system in the geographical valley of the Cauca river is based on the oxidizable organic carbon content determined by the Walkley-Black methodology. Subsequently, the organic carbon is multiplied by a constant that in the case of the Cenicaña soil laboratory is 1.76 to estimate the content of organic matter in the soil. According to the quantification of organic matter, soil drainage (good, poor or very poor) and the crop cycle (template or soca), the N dose to be applied to the crop is recommended.

Cenicaña evaluates the use of analysis methodologies that allow quantifying the fraction of organic matter that can rapidly provide mineralizable N and thus add nitrogen fertilizers in the appropriate dose when necessary. At the same time, the fraction of labile C contained in the organic matter of the soil is being studied since this fraction is a potential source of energy rapidly available to the soil microorganisms that are largely responsible for the mineralization of the organic matter in the soil. The objective of these studies is to optimize the use of nitrogen fertilizers, to maximize the profitability of the fertilization work and minimize the risk of environmental impact from excessive use of nitrogen fertilizers.

Spatial distribution of organic matter in the soil